The
Effect of Statistical Fluctuations of Solar Radiation on PV-System Sizing

S. Kaplanis and E. Kaplani (Greece)

Keywords

Solar radiation, PV-systems, PV-sizing, energy
fluctuations

Abstract

To cope with the uncertainty in weather conditions,
especially in solar radiation, the PV sizing methodology
has adopted the determination of the energy independence
period of d days in PV stand-alone systems. d depends on
the minimum value of the Peak Solar Hour (PSH) at a
place and for the month which is used as a reference for
the sizing process. This research study uses recorded data
to investigate the statistical fluctuations of solar radiation
for a day nj, as well as for a period of nj ± 2 days, with nj
being the day whose solar radiation records are used for
the sizing process. The current study gives a new
approach to the PV sizing issue, leading to a considerable
reduction in the estimated PV Peak Power, compared to
results obtained by previous methodologies encountered
in the literature. A similar reduction is achieved in the
battery storage system capacity, for a stand-alone PV
system, required to meet the loads for a number of d days.